Dear Neil: What is going on with our sago palm? It’s growing in this bizarre way with at least a dozen new heads. What should I do?

This is called fasciation, where cells divide in two planes instead of in all directions. You’re used to seeing it in the garden flower called cockscomb, and you may have noticed it on new growth of Texas mountain laurel. If you collect succulents, there are many euphorbias that develop this growth. It’s much less common with sago palms. My best advice is just to let it go ahead and play out. It will get more and more interesting, but it will end up destroying the plant.

Dear Neil: I have a large pecan tree that is dropping leaves. Many of them have swollen growths on their blades. What are those, and how can I stop them from damaging any more of the leaves?

Those are pecan phylloxera galls, and they’re basically harmless to the tree overall. They’ll knock off some of the leaves, but the tree will move on just fine. Dormant (horticultural) oil spray applied in January will kill a good number of them in their over-wintering form, but there is nothing you can do about them at this point.

Dear Neil: My bluebonnet patch has spread into the crushed granite path in our front yard. I don’t mind having them there, because as they go to seed I gather the seeds and replant them elsewhere. However, weeds come up with them. Is there any kind of weedkiller I can use that will eliminate the weeds without hurting the bluebonnets?

There is no weedkiller that is that selective. Probably your best bet is to draw a dividing line, and just define where you want the bluebonnets and where they won’t be allowed to grow. That way you’ll be able to keep weeds out of your walk and keep things looking a lot better groomed.

Dear Neil: A friend offered me a start of variegated cane. Is it as invasive as golden bamboo?

No, not even close. It’s a handsome, large grass if you have a spacious perennial garden where you can plant it in the back. I’d still contain it in some way, but it’s a very pretty plant. My observation has been that it does revert to the green form. You want to dig the green growth out, or it will overtake your variegated planting.

Have a question you’d like Neil to consider? Email him at mailbag@sperrygardens.com. Neil regrets that he cannot reply to questions individually.